Does your city allow you to build a little house in your backyard — an "accessory dwelling unit"?

Madison, Wisconsin does. Here we see a couple that has a house, and they're building a tiny house behind it, on the footprint of what had been a detached garage, 12 x 18. Then, they bring in tenants and make income for a while, and ultimately, as they age and no longer can or want to manage the big house, they move into the tiny house.

"We thought we might live in it when we're too old to live in the larger house... It's a way for us to stay in the neighborhood and live here."

"I've always liked the idea of living smaller and more beautifully... This idea is pretty neat."

So what do you think? Is this a great way to increase density in the city, build up the tax base, free people to make income from their property, provide appropriate housing for younger and older people, and boost the tiny house movement? Or is this a bad intrusion onto existing neighborhoods, pitting homeowners against each other?

I look out on our backyard and see 4 detached garages impinging on our view. Would we be worse off if those were converted into little houses? Put the cars in the driveways or on the street, and install little old couples or singles into those spaces. Or maybe Meade and I should build our perfect little dream house in our backyard, then sell the big house to new owners who will loom over us until we move on to the ultimate truly tiny house.